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- Effects of Melatonin-aided therapy on the Glutathione antioxidant system activity and liver protectionPublication . Popov, Serguey S.; Shulgin, Konstantin K.; Popova, Tatyana N.; Pashkov, Aleksander N.; Agarkov, Aleksander A.; Carvalho, Miguel A. A. Pinheiro deAcute hepatitis results from oxidative stress triggered by hepatotoxic drugs causing liver injury and the activation of caspases cascade. The glutathione antioxidant system protects against reactive oxygen species and mitigates development of these processes. The effectiveness of silymarin, a polyphenolic flavonoid, essenthiale, composed of phosphatidyl choline, and melaxen, a melatonin-correcting drug, as hepatoprotectors has been investigated. The variation of 6-sulfatoxymelatonin (aMT6s), resulting from the biotransformation of melatonin, and GSH has been measured. The activities of caspase-1 and caspase-3, glutathione antioxidant system, and NADPH-generating enzymes were determined. The aMT6s decreases in patients with drug hepatitis and recovers with administration of mexalen. GSH increased in the presence of the studied hepatoprotectors. Pathologically activated caspase-1 and caspase-3 decreased their activities in the presence of hepatoprotectors with melaxen showing the highest effect. The positive effect of melatonin appears to be related to the suppression of decompensation of the glutathione antioxidant system functions, recovery of liver redox status, and the attenuation of inhibition of the NADPH supply.
- Contributo para o conhecimento da agrodiversidade no concelho de Santa Cruz, MadeiraPublication . Carvalho, Miguel A. A. Pinheiro de; Ragonezi, Carla; Macedo, Fabrício Lopes de; Antunes, Gonçalo; Freitas, Gregório; Nóbrega, HumbertoO presente trabalho procura analisar as alterações sofridas pela agrodiversidade no território do Santa Cruz. Este concelho localizado na costa sul da Madeira tem 81,5 km2, quatro patamares bioclimáticos e numerosas unidades agroecológicas (UAE). A evolução da agrodiversidade iniciou-se, com o povoamento do Arquipélago, descoberto inabitado em 1418. A agrodiversidade biofísica, específica e intraespecífica aumentou e diversificou-se, devido à construção de agrossistemas, introdução de culturas, sucessão de ciclos agrícolas, adaptação às condições agroecológicas, aparecimento de pragas e doenças e pela ação do homem. Os registos históricos indicam a introdução de um elevado número de culturas, bem como a utilização de 72 espécies agrícolas, no concelho. E, indicam como fundamentais no povoamento e economia as culturas do trigo e as cerealíferas (cevada, centeio), cana-sacarina, vinha e sumagre. Várias outras culturas desempenharam um papel importante na economia do concelho, sendo cultivadas para fins alimentares, comerciais, industriais, culturais ou religiosos. A adaptação destas espécies aos agrossistemas e às condições agroecológicas deu origem a um número indeterminado de variedades locais. Apesar das limitações da documentação disponível, foram encontradas referências a variedades locais cuja cultura remonta há 140 a 500 anos, nomeadamente o Trigo da Serra, castas Malvasia e Tinta Antiga de Gaula, pêra Caniça, Banana da terra, feijão Corno de carneiro e Couve de João Ferino, que podem ser relacionadas com o historial do concelho. Porém, desde meados do século XX, a agrodiversidade sofreu uma drástica redução com a diminuição das áreas cultivadas, o abandono de várias espécies agrícolas e a extinção de variedades locais. A análise desta agrodiversidade foi realizada, a fim de apurar as alterações históricas e geográficas ocorridas na agrodiversidade em onze culturas representativas do concelho, visando a sustentabilidade agronómica.
- Prediction of the Potential Distribution of Drosophila suzukii on Madeira Island Using the Maximum Entropy ModelingPublication . Macedo, Fabrício Lopes; Ragonezi, Carla; Reis, Fábio; Freitas, José G. R. de; Lopes, David Horta; Aguiar, António Miguel Franquinho; Cravo, Délia; Carvalho, Miguel A. A. Pinheiro deDrosophila suzukii is one of the main pests that attack soft-skinned fruits and cause significant economic damage worldwide. Madeira Island (Portugal) is already affected by this pest. The present work aimed to investigate the potential distribution of D. suzukii on Madeira Island to better understand the limits of its geographical distribution on the island using the Maximum Entropy modeling (MaxEnt). The resultant model provided by MaxEnt was rated as regular discrimination with the area under the curve (AUC, 0.7–0.8). Upon scrutinizing the environmental variables with the greatest impact on the distribution of D. suzukii, altitude emerged as the dominant contributor, with the highest percentage (71.2%). Additionally, elevations ranging from 0 to 500 m were identified as appropriate for the species distribution. With the results of the model, it becomes possible to understand/predict which locations will be most suitable for the establishment of the analyzed pest and could be further applied not only for D. suzukii but also for other species that hold the potential for substantial economic losses in this insular region.
- Different seaweeds use for iodine deficiency overcomePublication . Ferraz, Sónia; Ragonezi, Carla; Nunes, Nuno; Valente, Sofia; Carvalho, Miguel A. A. Pinheiro deIodine deficiency is one of the three most common nutritional deficiencies worldwide and is a global public health problem that affects particularly the young children, pregnant women and elderly. The consequences of iodine deficiency disorder (IDD) include goiter and cretinism. The traditional consumption of iodine via supplemented salt should be monitored to reduce population sodium intake due to hypertension problems and the uncertain bioavailability of iodine in the supplemented salt. One approach for an effective and cost-efficient iodine supplementation is the use of seaweeds in food intake. Seaweeds, among all foods, are the most famous and reliable source of natural iodine. In this minireview we pretend to explore the different uses of seaweeds to fill the iodine deficiency and improve life quality.
- Screening for drought tolerance in thirty three Taro cultivarsPublication . Ganança, José F. T.; Freitas, José G. R.; Nóbrega, Humberto G.M.; Rodrigues, Vanessa; Antunes, Gonçalo; Gouveia, Carla S. S.; Rodrigues, Miguel; Chair, Hana; Carvalho, Miguel A. A. Pinheiro de; Lebot, VincentTaro [Colocasia esculenta (L.) Schott] is a root crop which is an important staple food in many regions of the world, producing 10.5 million tonnes on 1.4 million hectares a year. The crop is cultivated in wet (rain fed) or irrigated conditions, requiring on average 2,500 mm water per year, and in many countries it is cultivated in flooded plots. It is estimated that taro production could decrease by 40% as a result of the increase in drought and other severe events. In this work, thirty three accessions, including local cultivars, selected and hybrid lines were submitted to long duration drought stress and screened for tolerance. Twelve physiological, morphological and agronomic traits were measured at harvest, and subject to multivariate analysis. Stress indices, Water Use Efficiency and Factorial Analysis were useful for discriminating accessions regarding drought tolerance and yield stability, and drought tolerant and susceptible cultivars were identified. Our results confirm that different taro cultivars have different drought avoidance and tolerance strategies to cope with water scarcity. Better yield performers minimised biomass and canopy loss, while tolerance was observed in cultivars that presented low potential yield, but efficiently transferred resources to enhance corm formation. Among the 33 accessions, two local cultivars showed high yield stability and could be considered as suitable parents for breeding programs, while two others are well adapted to drought, but with overall low yield potential.
- Ecology and diversity of Solanum trisectum Dunal from Madeira Island: implications for Its conservationPublication . Alves, Sónia Ferraz; Reis, Fábio; Henriques, Dina; Freitas, Gregório; Gouveia, Carla S.S.; Fernandes, Francisco Manuel; Carvalho, Miguel A. A. Pinheiro deSolanum trisectum Dunal is an endemic Solanaceae of Madeira Island (Portugal), considered critically endangered due to its extreme rarity. Since its discovery this species has shown a narrow distributional range mainly on the northern side of the island, with scattered and small populations and large time gaps between sightings. The present work aimed to understand the underlying ecological underpinnings for this species rarity towards an effort to increase the success of conservation actions. Data on historical locations, environmental conditions field surveys, reinforcement in situ and ex situ germination trials were obtained. The species was found to currently occur only in two wild populations and two reinforcement sites, amounting to twenty-four plants in total. Statistical analysis of these data related wild populations and successful reinforcement sites, separating them from other sites where the reinforcement did not succeed. This suggests that the successful reinforcement sites showed conditions more similar to wild population sites compared to non-successful ones. The data obtained supports the hypothesis that S. trisectum distribution and rarity is determined by species specific habitat needs, i.e., abiotic conditions, which have been for the first time assessed during the present work. Further, this study also reinforces the classification of S. trisectum as a top priority species for conservation.
- Cereal landraces genetic resources in worldwide GeneBanks. A reviewPublication . Carvalho, Miguel A. A. Pinheiro de; Bebeli, Penelope J.; Bettencourt, Eliseu; Costa, Graça; Dias, Sonia; Santos, Teresa M. M. dos; Slaski, Jan J.Since the dawn of agriculture, cereal landraces have been the staples for food production worldwide, but their use dramatically declined in the 2nd half of the last century, replaced by modern cultivars. In most parts of the world, landraces are one of the most threatened components of agrobiodiversity, facing the risk of genetic erosion and extinction. Since landraces have a tremendous potential in the development of new cultivars adapted to changing environmental conditions, GeneBanks holding their genetic resources potentially play an important role in supporting sustainable agriculture. This work reviews the current knowledge on cereal landraces maintained in GeneBanks and highlights the strengths and weaknesses of existing information about their taxonomy, origin, structure, threats, sampling methodologies and conservation and GeneBanks’ documentation and management. An overview of major collections of cereal landraces is presented, using the information available in global metadatabase systems. This review on winter cereal landrace conservation focuses on: (1) traditional role of GeneBanks is evolving beyond their original purpose to conserve plant materials for breeding programmes. Today’s GeneBank users are interested in landraces’ history, agro-ecology and traditional knowledge associated with their use, in addition to germplasm traits. (2) GeneBanks therefore need to actively share their germplasm collections’ information using different channels, to promote unlimited and effective use of these materials for the further development of sustainable agriculture. (3) Access to information on the 7.4 million accessions conserved in GeneBanks worldwide, of which cereal accessions account for nearly 45 %, particularly information on cereal landraces (24 % of wheat, 23 % of barley, 14 % of oats and 29 % of rye accessions), is often not easily available to potential users, mainly due to the lack of consistent or compatible documentation systems, their structure and registration. (4) Enhancing the sustainable use of landraces maintained in germplasm collections through the effective application of recent advances in landrace knowledge (origin, structure and traits) and documentation using the internet tools and data providing networks, including the use of molecular and biotechnological tools for the material screening and detection of agronomic traits. (5) Cereal landraces cannot be exclusively conserved as seed samples maintained under ex situ conditions in GeneBanks. The enormous contribution of farmers in maintaining the crop and landraces diversity is recognised. Sharing of benefits and raising awareness of the value of cereal landraces are the most effective ways to promote their conservation and to ensure their continued availability and sustainable use. (6) Evaluation of costs and economic benefits attributed to sustainable use of cereal landraces conserved in the GeneBanks requires comprehensive studies conducted on a case-by-case basis, that take into consideration species/crop resources, conservation conditions and quality and GeneBank location and functions.
- Manual técnico da macieiraPublication . Antunes, Gonçalo; Freitas, Graça; Freitas, Gregório; Nóbrega, Humberto; Freitas, Isabel Tomás; Neto, Manuel; Rodrigues, Miguel; Dantas, Luís Miguel; Nunes, Rui; Carvalho, Miguel A. A. Pinheiro de
- Pharmacological and cosmeceutical potential of Seaweed Beach-Casts of MacaronesiaPublication . Zárate, Rafael; Portillo, Eduardo; Teixidó, Sílvia; Carvalho, Miguel A. A. Pinheiro de; Nunes, Nuno; Ferraz, Sónia; Seca, Ana M. L.; Rosa, Gonçalo P.; Barreto, Maria CarmoSeaweed beach-casts are a seasonal phenomenon that regularly deposits tons of algae biomass on beaches, which are usually disposed of in landfills. The present work aimed to contribute to the valorization of this biomass by studying bioactivities that reveal its potential in the pharmaceutical and/or cosmeceutical industries. Methanol and ethanol extracts and fractions from 15 beach-casts biomass were tested for a range of bioactivities. Eight of the most active samples exhibit IC50 values between 11.38 µg/mL and 19.28 µg/mL and selectivity indexes higher than 3.8, against NCI-H1299 (lung cancer) and T47D (breast cancer). Concerning antiaging potential, all the extracts tested presented UV protection, with SPF values above 30, like the standard sunscreen. Regarding aging-related enzymes, 24 samples were tyrosinase inhibitors exhibiting IC50 values from 9.01 µg/mL to 200.09 µg/mL. Eight extracts inhibited collagenase (IC50 < 248.76 µg/mL), two of them more actively than positive control EDTA (IC50 = 59.26 µg/mL). In addition to UV protection, the cumulative effect of antityrosinase and anticollagenase activities shown by the samples suggest that they may play a significant role in preventing skin photoaging. The results obtained demonstrate the high potential of beach-cast seaweed biomass as sources of cosmetic bioproducts with antiaging effects, and of selective cytotoxic metabolites.
- From a heavy metal perspective, is macroalgal biomass from Madeira Archipelago and Gran Canaria Island of eastern Atlantic safe for the development of blue bioeconomy products?Publication . Nunes, Nuno; Ferraz, Sónia; Venuleo, Marianna; Barros, Ana I. R. N. A.; Carvalho, Miguel A. A. Pinheiro deMacroalgae are considered a valuable source of several compounds with nutritional, nutraceutical, cosmeceutical, and phar maceutical applications. They are also used for crop fertilization and biofortifcation by introducing important minerals into the soil essential for crop productivity. At the same time, however, they are known bio-accumulators of some heavy metals. In this work, we assessed the content of 7 minerals considered as heavy metals in 25 macroalgae samples, comprising 4 greens, 9 reds and 12 browns, from Madeira Archipelago, Portugal, for their potential use as blue bioeconomy products. These heavy metals included zinc (Zn) with concentrations that ranged from 1.95 – 242.65 mg kg−1 dw, nickel (Ni, 0.6 – 34.78 mg kg−1 dw), copper (Cu, 0.42 – 7.98 mg kg−1 dw), chromium (Cr, 0.47 – 45.74 mg kg−1 dw), cadmium (Cd, 0.1 – 2.58 mg kg−1 dw), lead (Pb, 0.05 – 2.79 mg kg−1 dw) and mercury (Hg, 0.03 – 8.49 µg kg−1 dw). We also analysed 22 samples of beach-cast macroalgae from Gran Canaria Island, Spain, collected from November 2016 to November 2019. The same heavy metals were assessed with their concentrations that ranged as follows: Zn (11.41 – 42.20 mg kg−1 dw), Ni (3.17 – 17.78 mg kg−1 dw), Cu (1.85 – 4.20 mg kg−1 dw), Cr (6.08 – 37.98 mg kg−1 dw), Cd (0.02 – 0.11 g kg−1 dw), Pb (0.16 –5.42 mg kg−1 dw) and Hg (3.59 – 31.00 µg kg−1 dw). These concentrations are all within the normal ranges reported in earlier studies in low industrialized areas, except for the brown algae Gongolaria abies-marina and Sargassum vulgare with high mean (±SD) Cd concentration (1.91±0.36 and 1.75±0.07 g kg−1 dw respectively). Our results suggest that most of the biomass prospected in these localities covered in the present study would be a viable source of materials for the development of a blue economy industry with emerging products following the European Union directives.